I have noticed that the tranny seems to shift hard when shifting from 1-2. I say it is hard shifting with a noticeable jolt compared to our 2008 Tahoe Z71 (also 4wd). Only real difference is the tranny- 4sp vs the 6sp.

Is this expected? I have no idea what differences there are between the two mechanically other than the obvious 6sp gear-box. Wondering if there are significant changed in the programming involved with the two.

shouldnt be shifting hard that new. with the tow haul button pushed they shift is a little firmer but shouldnt be bad. would suck if there was something wrong with the solenoid valves already. its under warranty, id take it to the dealer. If he tells you its normal then test drive another similar truck on the lot to compare.

I have a 2010 Silverado quad Texas Edition with 5.3L and heavy duty 6 speed transmission. It has 4,500 miles on it and has developed a hard shift between 1st and 2nd and when stopping. It clanks terribly at times, but the rough shifting is getting to be almost constant. It's going into the dealer right after Christmas. There are a number of discussions going on at other sites (edmunds.com for example) with people who have 2009-2011's with similar issues. Today mine actually learched forward toward oncoming traffic as I crossed a divided highway and had to stop in the middle. Fortunately my foot was on the brake. This all started a week ago. I am not driving it any more till I can get it into the dealer.

I had the chance to drive another brand-new 2011 truck with the same engine/tranny combo. Acted the same so I figure it is "normal" but it is much different compared to the '08 Tahoe with the 4sp auto...

I had the chance to drive another brand-new 2011 truck with the same engine/tranny combo. Acted the same so I figure it is "normal" but it is much different compared to the '08 Tahoe with the 4sp auto...

Thanks for the reply and post back what is going on with your truck!

/r

Warren Allen

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I have a 2010 Silverado 1500 LT Crew Cab with the 5.3L and 6 spd auto. It has a hard 1-2 shift about 50% of the time. And then a hard 2-1 downshift when coming to a stop at lights at less the 25% of the time. Doesn't seem like anything is wrong at all, truck doesn't sound like its complaining when it occurs either. I think its just a difference in the gearing between 1st and 2nd and it hits a different spot in the powerband that makes it a noticeable shift compared to others. Just my .02 but since mine has 24k miles on it and still going strong, I have yet to worry about it :glasses:

Hey Guys, I'm a newb to the forum, but I am having the same issues with my 2010 GMC Sierra. Started at 2K miles and has been in the shop 4 times to locate and correct the problem. Unfortunately, the dealership has yet to recreate the problem even though it happens while I am pulling of the lot. We have investigated the slip yoke, rear end, even looked at engine mounts. The only theory we have come up with is the torque converter is spooling up and when the power is applied is CLUNKS into the correct setting. Needless to say I am not sold on the theory and really upset by the problem. Good luck to everyone and please post something if a solution is found.

i think this was covered a long while back with the 09 6spd. nothin really to worry about. bc it has 6 gears and 1st is as low as it is its just how it shifts. unless its grinding or making a noise you should be fine